The Constantinian Labarum and the Christianization of Roman Military Standards

In this paper I will address the labarum, a war standard introduced by Constantine the Great, and the problem of the Christianization of the Roman military signs between Constantine’s reign (306-377 AD) and the Theodosian period (379-457). Many scholars have referred to the labarum, but usually indirectly when discussing Constantine’s conversion. There are several open questions and gaps in our knowledge regarding this emblem, and I will attempt to answer some of them. First, this paper refers briefly to the precedents of military and religious standards in Antiquity and Pagan Rome. Then, it explores the origins, form, function and meaning of the labarum under Constantine and his successors through the literary and iconographic sources. The labarum started as symbol of victory granted by an ambiguous “supreme divinity”, and towards the last decades of Constantine’s reign the interpretation of it as a Christian apotropaic sign became dominant. Constantine’s successors used the labarum as a declaration of continuity, and the standards caused controversy under Julian the Apostate. Finally, this paper addresses the transformation of the standard under the house of Theodosius. I argue that in this period the cross surpassed the Chi-Rho symbol and the labarum-cross became the main banner of the Christian Roman Empire